The objective of this research is to define structural and functional features of the epididymis and sex accessory glands that are related to the maturation and transport of sperm, and to determine the ways in which these may be altered by antifertility agents. The studies will be carried out in the rat using light and electron microscopy, electron microscope radioautography, and electron-opaque tracers. Secretion of glycoproteins in the epididymis will be investigated following the administration of radioactive sugars. Cellular sites of synthesis, transport, and release of secretory material and its fate within the lumen of the epididymis will be determined. The pattern of regional differences in the epididymis and the roles of the different cell types in the epididymal epithelium with respect to secretion absorption and synthetic activities will be determined. Factors in the development and maintenance of regional specializations in the epididymis will be investigated, including the roles of fluid and sperm from the testis, androgen stimulation, and the scrotal environment. The secretory process in the prostate, seminal vesicles, and bulbourethral glands will be analyzed using electron microscope radioautography after the administration of precursors to the carbohydrate-rich components of their secretions. The effect of selected antifertility agents on secretion and absorption in the epididymis and sex accessory glands will be studied, including the influence of antiandrogens and gonadotropin-inhibiting compounds. The effects of testosterone enanthate and of the antiandrogen Flutamide on the ultrastructure of the testis and sex accessory organs will be determined.